GISTutorialFeb2013 - University of Arkansas Libraries

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Intro to ArcGIS
Kate Dougherty, Geosciences & Maps Librarian
Tutorial created for version 10.1 in February 2013
Overview
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What is GIS?
Common uses
Software
Interface & navigation
Adding layers
Customizing &
displaying layers
• Select features by
attribute
• Select features by
location
• Buffer features tool
• Layout view
• Datums & projections
• File management
• Data sources
What is GIS?
• Geographic Information Systems (GIS) is a
computer-based methodology for collecting,
managing, analyzing, modeling, and
presenting geographic or spatial data.
• Allows you to overlay datasets and query
them in terms of their spatial relation to each
other
Two Types of Spatial Data
• Raster - continuous data
– E.G., air photos, scanned maps, elevation layers
– Most remote sensing data is raster data
• Vector - discrete features
– A layer comprised of individual points, lines or
polygons (e.g., roads or states)
– This presentation focuses on vector data
Common Uses
• Analyzing potential environmental hazards
• Emergency services planning and routing
• Siting new facilities:
– wind farms
– power plants
– vineyards
• Identifying food deserts in urban areas
• Much more!
Esri
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Environmental Systems Research Institute
ESRI is now Esri
Industry leader for GIS software
Program is ArcGIS/ArcMap
– Now up to version 10.1.
– (This presentation done with V. 10)
Table of
contents that
shows the
doc’s layers.
The “data frame” that displays the spatial data.
Go to full
map
extent
Go to
previous
extent
Go to
next
extent
Identify
feature
Select
features
(by hand)
Select
elements
(to move
or edit)
Clear
selected
features
Add data
Project:
Identify Washington County Parcels
Near Perennial Streams
Add Layers
• States (Census Bureau)
• Counties (Census Bureau)
• Hydrography (Area - National Hydrography
Dataset)
• Parcels (Washington County –
Wash_Co_Data_Month_Year.zip)
• Public lands (GeoStor)
Click to add data
Coordinate Systems
• All your layers may not necessarily use the
same coordinate system.
– OK to draw and display
– Not OK for detailed analysis
(need to reproject layers – advanced step)
• Data frame will use the coordinate system of
the first layer that’s added
– (displays feet, meters, or decimal degrees/lat/long
of cursor location in bottom-right corner,
depending on coordinate system)
View With All Layers Added
Zoomed to Washington County
Rename States Layer
State layer
renamed
Open the Attribute Table
Customizing Layers
Select by Attribute Tool
Selection is Highlighted
New Layer is Added to Map
Arkansas Only Remaining State
Changing the Display of Layers
• Change symbology/colors
• Turn individual layers on or off
• Change the display order
– Layers on map display according to their order in the
table of contents
– Top layers may hide features in layers under them
– Click & drag a layer in the table of contents to change
its display order on the map
Change the Display Order
Change Symbology of Layers
Change Color of Streams
New Symbologies Displayed
Clip Streams to Washington County
Clip Tool
Access Clip in Geoprocessing Menu
Clip Tool Dialog Box
Clip Tool Progress Indicator
Clip Completed Indicator
Change Symbology of New
Clipped Hydro Layer
New Clipped File Looks Great!
Analysis
• We will find parcels that:
– Contain perennial streams
And note their status in the parcel layer’s attribute
table.
Add New Columns to Attribute Table
Field Types
Whole Numbers
Decimals
• Short Integer
(integers from -32,768
to 32,767)
• Double
(up to 6 decimal places)
• Long Integer
(integers from 2,147,483,648 to
2,147,483,647)
• Float
(unlimited # of decimal
places)
Task: Select Parcels with a
Perennial Stream
View Selected in Attribute Table
View Selected Records Only
Task: Select Parcels in a “flood Zone”
Within a Distance of Perennial Streams
• Use the buffer tool to draw a “buffer zone”
around specified features
Manage Files with ArcCatalog
• File manager for files used in ArcMap
• Best to manage moving pieces this way,
instead of Windows Explorer
ArcCatalog Window
Use ArcCatalog to View Metadata
Share Maps and Layers with Packages
• Package up all the information used to create
a layer or map document for easy sharing by
email, a shared drive on the LAN, etc.
• Right-click a layer in the TOC and select
“Create Layer Package”
Share a Map Package
• To package up an entire map document for
sharing, use File | Create Map Package
ArcMap will force you to create some limited metadata before creating a
sharable package. Click OK.
Creating Packages
• Save the package as a file and share as you
usually would
• You must “validate” your package before
saving
– Detects any errors that would impede sharing
Validation
• Any errors need to be corrected. Click on any
error messages to see a help document.
• Warnings are warnings only – can go ahead
and publish.
• If no problems, the share button will become
active.
What Else Can You Do with GIS?
• Join stats based on
geography (i.e., states)
to a states GIS layer and
view the data spatially
– Excel, CSV, text formats
• Create/digitize your
own data
• import GPS data
• Analyze viewsheds and
shadows
• Use web map services
for mashups in your
own applications
• Much more!
GIS Software at University of Arkansas
• Reference desk machine (version 10.1)
• Campus-wide license – administered by the
Center for Advanced Spatial Technologies
(CAST)
• Free software
Sources of GIS Data
• Search for selected base layers (reference
maps) from right within the application
• GeoStor (Arkansas state portal)
• geo.data.gov (federal portal)
• National Map (USGS)
• TIGER/Census Shapefiles (reference layers –
boundaries, roads)
LibGuide
• The Maps, GIS and Remote Sensing LibGuide
can point you to:
– Information on how to get Esri software through
the campus license
– Resources for learning GIS
– Sources of GIS data (spatial and attribute)
Good luck!
Thank you!
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